The present invention relates to a work transfer apparatus for separating several works fed sequentially and transferring them one by one.
A known work transfer apparatus for transferring works such as IC chips on which electronic components are integrated, or electronic chips like a resistance, a condenser, or an inductor, is equipped with a work feeder for feeding works, a turn table formed with work-storing pockets at its outer periphery and a separation mechanism provided between the work feeder and the turn table.
Several works are sequentially fed by the work feeder and separated by the separation mechanism. The works are once stored in the work-storing pockets one by one and transferred to the next stage.
It is highly required that the works be completely separated from each other by the separation mechanism before being stored in the work-storing pockets because they are touching each other when sequentially fed by the work feeder.
Powder dust will be generated from, for example, electronic components vulnerable to friction when the components are separated by being pressed onto the passage wall or suction in a separation mechanism. Such powder dust attached on electrodes of the components could cause inferior conductivity after several processes and soil the components or any mechanism they are fed.
In view of the problems discussed above, a purpose of the present invention is to provide a work transfer apparatus with a separation mechanism in which works suffer the minimum friction during pressure- or suction-separation, the completely separated works being promptly transferred into work-storing pockets.
The present invention provides a work transfer apparatus including: a work feeder for feeding a plurality of works; a rotatable turn table with a plurality of work-storing pockets at the outer periphery of the turn table; and a separation mechanism provided with a communicating passage extending between the work feeder and the turn table, wherein the turn table is rotated by a driver to shift the work-storing pockets at a work-receiving position one by one, the work-receiving position facing the communicating passage, a suction opening being provided in the vicinity of the turn table so that the suction opening communicates with the work-storing pocket located at the work-receiving position, a work detector is provided in the vicinity of the turn table, for detecting the work stored in the work-storing pocket located at the work-receiving position; and a work stopper provided on the communication passage of the separation mechanism on an upstream side of the work detector, the work stopper being able to protrude into and be retracted from the communication passage, the work stopper being driven by a controller based on a signal from the work detector.
The work stopper may be provided along the communicating passage of the separation mechanism and in the vicinity of the outer periphery of the turn table.
The work stopper may include a separating pin and a pin-driving mechanism, the separating pin protruding into and being retracted from the communicating passage of the separation mechanism in the vicinity of the turn table by the pin-driving mechanism under control of the controller.
The work transfer apparatus may further include a pin detector in the vicinity of the separating pin, for detecting the separating pin while protruding into and being retracted from the communicating passage of the separation mechanism, the controller controlling the driver to rotate the turn table based on a signal from the pin detector.
In the work transfer apparatus, the work detector may include a photo emitter provided at a wall of the work-storing pocket at base or cover side and a photo receptor provided at an opposing wall of the work-storing pocket.
In the work transfer apparatus, in response to the signal from the work detector, the controller may drive the work stopper to protrude into the communication passage to separate the work in the work-storing pocket from other works when the work has been stored in the work-storing pocket located at the work-receiving position, whereas the controller may drive the work stopper to be retracted from the communication passage when no works have been stored in the work-storing pocket located at the work-receiving position.
In the work transfer apparatus, the separation mechanism and the turn table may be supported by a supporting base, and enclosed by a cover.
In the work transfer apparatus, the work stopper may include a separating pin provided on the supporting base or the cover, the separating pin being able to protrude into and be retracted from the communicating passage.
In the work transfer apparatus, the work detector may include a photo emitter provided at either the supporting base or the cover and a photo receptor provided at the other of the supporting base and the cover.
In the work transfer apparatus, the controller may halt the driver based on a signal from the pin detector when the separating pin has not protruded enough into the communicating passage.
In the work transfer apparatus, the pin detector may operate when a protrusion attached to the separating pin comes close to the pin detector.
According to the present invention, several works fed by the work feeder are sequentially transferred through the communicating passage. The preceding work is stopped by the separating pin of the work stopper stuck into the communicating passage. The separating pin is then retracted from the communicating passage so that the preceding work is stored in a work-storing pocket located at the receiving position on the turn table due to a negative pressure caused by suction through the suction opening. The work stopper is operated by the controller based on a signal from the work detector so that the separating pin is stuck into the communicating passage again to stop the succeeding work.